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1.
Cereb Cortex ; 34(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38629796

RESUMO

Neuroimaging studies have shown that the neural representation of imagery is closely related to the perception modality; however, the undeniable different experiences between perception and imagery indicate that there are obvious neural mechanism differences between them, which cannot be explained by the simple theory that imagery is a form of weak perception. Considering the importance of functional integration of brain regions in neural activities, we conducted correlation analysis of neural activity in brain regions jointly activated by auditory imagery and perception, and then brain functional connectivity (FC) networks were obtained with a consistent structure. However, the connection values between the areas in the superior temporal gyrus and the right precentral cortex were significantly higher in auditory perception than in the imagery modality. In addition, the modality decoding based on FC patterns showed that the FC network of auditory imagery and perception can be significantly distinguishable. Subsequently, voxel-level FC analysis further verified the distribution regions of voxels with significant connectivity differences between the 2 modalities. This study complemented the correlation and difference between auditory imagery and perception in terms of brain information interaction, and it provided a new perspective for investigating the neural mechanisms of different modal information representations.


Assuntos
Córtex Auditivo , Mapeamento Encefálico , Mapeamento Encefálico/métodos , Imaginação , Encéfalo/diagnóstico por imagem , Percepção Auditiva , Córtex Cerebral , Imageamento por Ressonância Magnética/métodos , Córtex Auditivo/diagnóstico por imagem
2.
J Phys Chem B ; 128(16): 3964-3971, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38602495

RESUMO

The properties and formation mechanisms of the triplet state have been widely investigated since they are crucial intermediates in photo functional devices. Specifically, helical PDI dimers, horizontal expanded π-conjugated derivatives of PDI, have shown outstanding performance as electron acceptors in enhancing the performance of photovoltaics. Therefore, the exploration of triplet generation in helical PDI dimers plays a crucial role in understanding the mechanisms and excavating their further application. We make use of Se-annulation to induce intersystem crossing (ISC) in helical PDI dimers and further explore the triplet evolution process systematically as the number of Se atoms increases by transient absorption spectroscopy and the hole-electron analysis method. It shows that the twisted molecular conformation has paved the way for potential ISC in a parent molecule PDI2. The incorporation of Se atoms can result in evident promotion in the efficiency of ISC (ϕTPDI2-2Se = 96.9%) compared to the parent molecule PDI2 (ϕTPDI2 = 26.5%), indicating that chalcogen-annulation is also an efficient strategy in a π-extended system. Our results provide useful insights for understanding the triplet evolution process, which can help broaden the application of the π-extended PDI system into high-performance photovoltaics.

3.
J Neurosci Res ; 102(2): e25297, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38361412

RESUMO

Genetic risk for schizophrenia is thought to trigger variation in clinical features of schizophrenia, but biological processes associated with neuronal activity in brain regions remain elusive. In this study, gene expression features were mapped to various sub-regions of the brain by integrating low-frequency amplitude features and gene expression data from the schizophrenia brain and using gene co-expression network analysis of the Allen Transcriptome Atlas of the human brain from six donors to identify genetic features of brain regions and important associations with neuronal features. The results indicate that changes in the dynamic amplitude of low-frequency fluctuation (dALFF) are mainly associated with transcriptome signature factors such as cortical layer synthesis, immune response, and expanded membrane transport. Further modular disease enrichment analysis revealed that the same set of signature genes associated with dALFF levels was enriched for multiple neurological biological processes. Finally, genetic profiling of individual modules identified multiple core genes closely related to schizophrenia, also potentially associated with neuronal activity. Thus, this paper explores genetic features of brain regions in the schizophrenia closely related to low-frequency amplitude ratio levels based on imaging genetics, which suggests structural endophenotypes associated with schizophrenia.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/genética , Esquizofrenia/metabolismo , Encéfalo/metabolismo , Transcriptoma , Perfilação da Expressão Gênica , Neurônios/metabolismo , Imageamento por Ressonância Magnética
4.
Am J Cancer Res ; 13(5): 1786-1805, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293168

RESUMO

The tumor immunosuppressive microenvironment plays an important role in tumor progression. Alcohol is well-known as a regulator of the immune system and several studies have also reported that chronic alcohol intake can activate the immune system. However, it is unclear whether alcohol can affect liver cancer progression by regulating the immunosuppressive microenvironment. In this study, we investigated the effects of different alcohol concentrations on the growth of liver cancer and tumor immune microenvironment. We examined the growth of tumors in mice provided with water, or alcohol (for 2 weeks before tumor injection, and for 3 weeks after tumor injection). We found that alcohol consumption at 5% and 20% inhibited the growth of subcutaneous tumors in hepatocellular carcinoma-bearing mice, whereas 2% alcohol concentration did not significantly inhibit liver cancer growth. The ratio of myeloid-derived suppressor cells (MDSCs) in peripheral blood and spleen of mice treated with 5% or 20% alcohol for 2 weeks before tumor inoculation was downregulated. After tumor inoculation, the proportion of MDSCs in peripheral blood, spleen, and tumor of mice treated with 5% or 20% alcohol for another 3 weeks also decreased and the proportion of CD4+ T cells and CD8+ T cells increased. In addition, Alcohol consumption of 20% reduced levels of the inflammatory factor IL-6 by inhibiting JAK/STAT3 signaling. These results indicate that chronic alcohol consumption may inhibit the growth of liver cancer by regulating MDSCs.

5.
Int Immunopharmacol ; 121: 110413, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37301119

RESUMO

Hepatocellular carcinoma is characterized by a high infiltration of myeloid-derived suppressor cells (MDSC), which are key drivers of maintaining the immunosuppressive tumor microenvironment. Therefore, targeting MDSCs will improve immunotherapies for cancers. It has been shown that all-trans retinoic acid (ATRA) can differentiate MDSCs into mature myeloid cells. However, whether ATRA suppression of MDSCs function could inhibit the growth of liver cancer remains unknown. Here we found that ATRA significantly inhibited hepatocellular carcinoma promotion, tumor cell proliferation, and angiogenesis markers. Moreover, ATRA decreased the number of mononuclear myeloid-derived suppressor cells (M-MDSCs), granulocytic myeloid-derived suppressor cells (G-MDSCs) and tumor-associated macrophages (TAMs) in spleens. In addition, ATRA significantly reduced the intratumoral infiltrating G-MDSCs and the expression of protumor immunosuppressive molecules (arginase 1, iNOS, IDO and S100A8 + A9), which was accompanied by increased cytotoxic T cell infiltration. Our study demonstrates that ATRA not only has direct intrinsic inhibitory effect on tumor angiogenesis and fibrosis, but also reeducates the tumor microenvironment toward an antitumor phenotype by altering the relative proportion between protumor and antitumor immune cells. This information introduces ATRA as a potential druggable target for treatment of hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células Supressoras Mieloides , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Tretinoína/farmacologia , Células Mieloides , Microambiente Tumoral
6.
J Mol Neurosci ; 72(10): 2094-2105, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36006583

RESUMO

Depression is characterized by poor emotion regulation that makes it difficult to escape the effects of emotional pain, but the neuromodulation behind these symptoms is still unclear. This study investigated the neural mechanism of emotional state-related responses during music stimuli in participants with major depressive disorder (MDD) compared to never-depressed (ND) controls. A novel two-level feature selection method, integrating recursive feature elimination based on support vector machine (SVM-RFE) and random forest algorithm (RF), was proposed to screen emotional recognition brain regions (ERBRs). On this basis, the differences of functional connectivity (FC) were systematically analyzed by two-sample t-test. The results demonstrate that ND participants show eight pairs of FCs with a significant difference between positive emotional music stimuli (pEMS) versus negative emotional music stimuli (nEMS) in 15 ERBRs of MDD, but the participants with MDD show one pair of significant difference in FC. The decreased number reflects the fuzzy response to positive and negative emotions in MDD, which appears to arise from obstacle to emotional cognition and regulation. Furthermore, there was no significant difference in FC between MDDs and NDs under pEMS, but a significant difference was detected between the two groups under nEMS (p < 0.01), revealing a 'bias' against the negative state in MDD. The current study may help to better comprehend the abnormal evolution from normal to depression and inform the utilization of pEMS in formal treatment for depression.


Assuntos
Transtorno Depressivo Maior , Música , Humanos , Transtorno Depressivo Maior/terapia , Imageamento por Ressonância Magnética/métodos , Encéfalo , Emoções/fisiologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-35432562

RESUMO

Background: Licorice is one of the most ubiquitous herbs in traditional Chinese medicine, with notable anti-inflammatory and antiulcerative effects as well as potent digestive disease therapeutic impacts; yet, its active components and mechanisms remain unclear. There is a lot of evidence that Glycyrrhiza polysaccharide (GPS) has antioxidants, improving intestinal flora, anti-inflammatory effects, etc. Hypothesis/Purpose. Here, we investigated the effects of GPS on dextran sulfate sodium (DSS)-induced acute ulcerative colitis (UC) mice and its possible mechanisms. Methods: GPS (100, 200, and 400 mg/kg) or the positive control drug sulfasalazine (SASP) (200 mg/kg) were orally administered to mice for 8 days. Body weight was recorded daily. Symptoms associated with UC, such as disease activity index (DAI), colon length, spleen weight, and mucosal damage were detected. The possible mechanism of GPS ameliorating enteritis symptoms was explored by detecting intestinal permeability and serum levels of inflammatory factors, and changes in intestinal permeability were expressed by serum concentration of FITC-dextran and D-lactic acid. Results: The results demonstrated that GPS administration alleviated UC symptoms in colitis mice, including weight loss, DAI index, shorting colon length, and mucosal damage. Mechanistic evaluation revealed that GPS treatment reduced intestinal permeability and serum levels of inflammatory factors: IL-1, IL-6, and TNF-α, while increasing serum levels of the anti-inflammatory factor IL-10, suggesting that GPS's mechanism in UC is related to reducing intestinal permeability and inhibiting the inflammatory response, with intestinal permeability implicated as the initiating mechanism. Conclusion: This study highlights GPS as a promising therapeutic agent, with high therapeutic efficacy and a good safety profile, for enteritis and beyond.

8.
Sci Total Environ ; 795: 148886, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34247077

RESUMO

Plastic film mulching has been extensively used for spring maize (Zea mays L.) production in the Hetao Irrigation District (HID). Determining whether transparent plastic film mulching results in premature senescence and yield reduction of spring maize still needs to be verified. A two-year field experiment was conducted in the HID that involved planting spring maize under three mulching practices on a flat plot 1) without mulching (control treatment, CK), 2) with black plastic film mulching (BM), 3) with transparent plastic film mulching (TM). The results indicated that TM and BM were superior to CK in terms of effects on soil hydrothermal conditions. Compared with BM, TM produced significantly higher soil temperature at V6, and had no significant temperature effect at V12, R1, R3, and R6. Both TM and BM promoted early seedling emergence and earlier silking, and TM extended the duration of the reproductive stages by 1-2 days compared with BM, and 4-5 days longer than CK. TM and BM produced greater kernel weights and kernel volumes in the superior and middle portions of the ear than CK. TM produced significantly greater total kernel weights per ear than BM at and after 23 days after silking. TM significantly increased grain-filling rate and length of the active grain-filling period compared with BM and CK. Additionally, TM and BM produced significantly higher photosynthetic parameters than CK at the grain-filling stage in the two study years. The net photosynthesis rate for TM was significantly greater than for BM. TM and BM significantly increased grain yields by 28.1% and 15.1%, respectively, in 2019 over CK, and by 24.6% and 21.1% in 2020. Transparent plastic film mulching could serve as a promising adaptive management practice to increase resource use efficiency and to improve maize productivity in the HID.


Assuntos
Plásticos , Solo , Agricultura , China , Água/análise , Zea mays
9.
Sci Total Environ ; 794: 148590, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34225153

RESUMO

The objective of this study was to calculate the carbon footprint (CF) of straw and plastic film mulching practices in order to identify the optimum field management for low-carbon agriculture. A four-year field experiment was conducted to determine the effects of different mulching measurements on greenhouse gas (GHG) emissions, grain yield, and CF of a winter wheat-summer maize cropping system in the Loess Plateau of China. Mulching treatments were no mulching (NM), straw mulching (SM), half plastic film mulching (HPM); full plastic film mulching (FPM), and ridge-furrow planting with film mulching over ridges (RPM). Plastic film mulching decreased N2O emissions compared with NM. However, SM significantly increased direct N2O emissions by 59.2% and indirect N2O emissions by 16.2%. Average annual total GHG emissions calculated by life cycle assessment were 5199-7631 kg CO2-eq ha-1 yr-1. Nitrogen (N) fertilizer was the largest contributor to total GHG emissions, accounting for >41%. For plastic film mulching treatments, the second greatest contributor was plastic film, accounting for 21.1-35.7% of total GHG emissions. In contrast, the second greatest contributor was direct and indirect N2O and CH4 emissions under NM (17.2%) and SM (21.6%). Emissions from diesel consumption was the third largest component of total GHG emissions. All mulching treatments showed significantly greater annual grain yield than the NM treatment. The CF of summer maize yield was higher than that of winter wheat. SM showed the lowest CF (0.38 kg CO2-eq kg-1), and plastic film mulching increased CFs compared with NM. These results suggest that SM should be the priority mulching practice used to increase yield and to reduce the CF of winter wheat-summer maize production in the Loess Plateau, China. Optimizing N fertilizer application rates should be one of the key production strategies employed to mitigate agricultural GHG emissions.


Assuntos
Triticum , Zea mays , Agricultura , Pegada de Carbono , China , Fertilizantes , Plásticos , Solo
10.
Huan Jing Ke Xue ; 39(11): 5246-5256, 2018 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628250

RESUMO

In order to evaluate the effect of different treatments on yield and greenhouse gas emissions during the summer maize growing season, a two-year film mulching experiment was conducted in 2014 and 2015. In this experiment, the two main experimental factors were rainfed treatment (R) and irrigated treatment (I), and the secondary experimental factors included control treatment (CK), half film mulching treatment (HM), and full film mulching treatment (FM). The emissions of soil greenhouse gases (CO2, CH4, and N2O) were monitored using a static opaque chamber and chromatography method. Moreover, the greenhouse gas emissions intensity (GHGI) was used to evaluate the effect of carbon sequestration in different treatments. The results of this study showed that the yields of the RHM and RFM treatments did not differ significantly in 2014, but increased by 19.6% and 26.8%, respectively, in 2015 compared with that of RCK. The yield of IHM was not improved, and that of IFM significantly increased by 14.1% and 55.8% in 2014 and 2015, respectively, compared with that of ICK. The irrigated treatments only promoted CO2 emissions in 2015 (P<0.01), and all film mulching treatments (regardless of HM and FM treatments) had no effect on CO2 emissions under rainfed and irrigated conditions (P>0.05). Irrigated treatments had no effect on the absorption of CH4 (P>0.05), whereas the film mulching treatments had an inhibitory effect. Compared with values of RCK, the amount of seasonal N2O emissions for ICK showed a significant difference in 2015 with a decrease of 22.3%. Compared with values of RCK, the amounts of N2O emissions for RHM and RFM had no significant differences in 2014, but significantly decreased by 50.7% and 51.4% in 2015, respectively. Compared with ICK, IHM and IFM significantly decreased the amounts of N2O emissions by 47.5% and 54.2% in 2014, and by 9.6% and 52.2% in 2015, respectively. The GHGIs of RHM and RFM were significantly reduced by 60.1% and 61.7% in 2015, respectively, compared with values of RCK, and the GHGIs of IHM and IFM were significantly reduced by 39.7% and 53.2% in 2014, and reduced by 22.2% and 67.5% in 2015, respectively, compared with that of ICK. This means that the effect of FM on reducing GHGI was better than that of HM. It was also found that the significantly reduced GHGI in irrigated treatments may be attributed to the increased yields. Therefore, FM under irrigation conditions was recommended for summer maize for stabilizing the yield and reducing the GHGI.


Assuntos
Agricultura/métodos , Gases de Efeito Estufa/análise , Plásticos , Zea mays/crescimento & desenvolvimento , Dióxido de Carbono/análise , Metano/análise , Óxido Nitroso/análise , Estações do Ano , Solo
11.
Eur J Paediatr Neurol ; 19(3): 280-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25662757

RESUMO

OBJECTIVE: To evaluate the efficacy of cervical perivascular sympathectomy (CPVS) for drooling in children with athetoid cerebral palsy (ACP). METHODS: The severity and frequency of drooling and the amount of salivation of 32 ACP children with drooling were evaluated before CPVS and at 4th, 12th and 24 weeks postoperatively by the teacher drooling scale (TDS) and salivary flow rate (SFR). RESULTS: Fifteen children exhibited improvements on drooling according to the TDS score at 4th week after surgery (P < 0.05). Later, the number of children decreased to 10 at 12th week (P < 0.05) and to 8 at 24 week after surgery (P < 0.05). SFR was 0.67 mg/min at baseline, which decreased to 0.58 mg/min (P < 0.05) at 4th week after surgery. However, SFR showed a gradual increase at 12th week and 24 week with no significant difference. CONCLUSIONS: Although CPVS was effective in improving drooling in some children with ACP, the results were not satisfactory. Thus, CPVS still needs to be cautiously used. Furthermore, more rigorous clinical studies should be performed to detect the effectiveness and safety of this procedure.


Assuntos
Paralisia Cerebral/complicações , Sialorreia/etiologia , Sialorreia/cirurgia , Simpatectomia/métodos , Paralisia Cerebral/cirurgia , Criança , Feminino , Humanos , Masculino
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